start refactoring: move daemon into subpackage

cmd/config_parse.go

@@ -137,13 +137,6 @@ func parseConfig(i interface{}) (c *Config, err error) {
 		c.Jobs[job.JobName()] = job
 	}
 
-	cj, err := NewControlJob(JobNameControl, jpc.Global.Control.Sockpath)
-	if err != nil {
-		err = errors.Wrap(err, "cannot create control job")
-		return
-	}
-	c.Jobs[JobNameControl] = cj
-
 	return c, nil
 
 }
@@ -201,8 +194,6 @@ func parseJob(c JobParsingContext, i map[string]interface{}) (j Job, err error)
 		return parseSourceJob(c, name, i)
 	case JobTypeLocal:
 		return parseLocalJob(c, name, i)
-	case JobTypePrometheus:
-		return parsePrometheusJob(c, name, i)
 	default:
 		panic(fmt.Sprintf("implementation error: unknown job type %s", jobtype))
 	}

cmd/config_serve_stdinserver.go

@@ -6,6 +6,7 @@ import (
 	"github.com/problame/go-netssh"
 	"net"
 	"path"
+	"github.com/zrepl/zrepl/cmd/helpers"
 )
 
 type StdinserverListenerFactory struct {
@@ -32,7 +33,7 @@ func parseStdinserverListenerFactory(c JobParsingContext, i map[string]interface
 
 func (f *StdinserverListenerFactory) Listen() (net.Listener, error) {
 
-	if err := PreparePrivateSockpath(f.sockpath); err != nil {
+	if err := helpers.PreparePrivateSockpath(f.sockpath); err != nil {
 		return nil, err
 	}
 

cmd/control.go

@@ -13,6 +13,8 @@ import (
 	"net"
 	"net/http"
 	"os"
+	"github.com/zrepl/zrepl/version"
+	"github.com/zrepl/zrepl/cmd/daemon"
 )
 
 var controlCmd = &cobra.Command{
@@ -48,7 +50,7 @@ var pprofCmd = &cobra.Command{
 	},
 }
 var pprofCmdArgs struct {
-	msg PprofServerControlMsg
+	msg daemon.PprofServerControlMsg
 }
 
 var controlVersionCmd = &cobra.Command{
@@ -107,7 +109,7 @@ func doControlPProf(cmd *cobra.Command, args []string) {
 		log.Printf("error marshaling request: %s", err)
 		die()
 	}
-	_, err = httpc.Post("http://unix"+ControlJobEndpointPProf, "application/json", &buf)
+	_, err = httpc.Post("http://unix"+daemon.ControlJobEndpointPProf, "application/json", &buf)
 	if err != nil {
 		log.Printf("error: %s", err)
 		die()
@@ -131,7 +133,7 @@ func doControLVersionCmd(cmd *cobra.Command, args []string) {
 		die()
 	}
 
-	resp, err := httpc.Get("http://unix" + ControlJobEndpointVersion)
+	resp, err := httpc.Get("http://unix" + daemon.ControlJobEndpointVersion)
 	if err != nil {
 		log.Printf("error: %s", err)
 		die()

cmd/daemon.go

@@ -4,12 +4,14 @@ import (
 	"context"
 	"fmt"
 	"github.com/spf13/cobra"
-	"github.com/zrepl/zrepl/logger"
 	"os"
 	"os/signal"
 
 	"syscall"
 	"time"
+	"github.com/zrepl/zrepl/cmd/daemon"
+	"github.com/zrepl/zrepl/cmd/daemon/job"
+	"github.com/zrepl/zrepl/logger"
 )
 
 // daemonCmd represents the daemon command
@@ -57,6 +59,20 @@ func (j JobType) String() string {
 	return string(j)
 }
 
+type daemonJobAdaptor struct {
+	j Job
+}
+
+func (a daemonJobAdaptor) Name() string {
+	return a.j.JobName()
+}
+
+func (a daemonJobAdaptor) Run(ctx context.Context) {
+	a.j.JobStart(ctx)
+}
+
+func (a daemonJobAdaptor) Status() interface{} { return nil }
+
 func doDaemon(cmd *cobra.Command, args []string) {
 
 	conf, err := ParseConfig(rootArgs.configFile)
@@ -66,13 +82,13 @@ func doDaemon(cmd *cobra.Command, args []string) {
 	}
 
 	log := logger.NewLogger(conf.Global.logging.Outlets, 1*time.Second)
-
-	log.Info(NewZreplVersionInformation().String())
-	log.Debug("starting daemon")
 	ctx := WithLogger(context.Background(), log)
 
-	d := NewDaemon(conf)
-	d.Loop(ctx)
+	daemonJobs := make([]job.Job, 0, len(conf.Jobs))
+	for i := range conf.Jobs {
+		daemonJobs = append(daemonJobs, daemonJobAdaptor{conf.Jobs[i]})
+	}
+	daemon.Run(ctx, conf.Global.Control.Sockpath, conf.Global.logging.Outlets, daemonJobs)
 
 }
 

cmd/daemon/control.go

@@ -1,4 +1,4 @@
-package cmd
+package daemon
 
 import (
 	"bytes"
@@ -9,15 +9,18 @@ import (
 	"io"
 	"net"
 	"net/http"
+	"github.com/zrepl/zrepl/cmd/daemon/job"
+	"github.com/zrepl/zrepl/version"
+	"github.com/zrepl/zrepl/cmd/helpers"
 )
 
-type ControlJob struct {
-	Name     string
+type controlJob struct {
 	sockaddr *net.UnixAddr
+	jobs *jobs
 }
 
-func NewControlJob(name, sockpath string) (j *ControlJob, err error) {
-	j = &ControlJob{Name: name}
+func newControlJob(sockpath string, jobs *jobs) (j *controlJob, err error) {
+	j = &controlJob{jobs: jobs}
 
 	j.sockaddr, err = net.ResolveUnixAddr("unix", sockpath)
 	if err != nil {
@@ -28,11 +31,9 @@ func NewControlJob(name, sockpath string) (j *ControlJob, err error) {
 	return
 }
 
-func (j *ControlJob) JobName() string {
-	return j.Name
-}
+func (j *controlJob) Name() string { return jobNameControl }
 
-func (j *ControlJob) JobType() JobType { return JobTypeControl }
+func (j *controlJob) Status() interface{} { return nil }
 
 const (
 	ControlJobEndpointPProf   string = "/debug/pprof"
@@ -40,14 +41,12 @@ const (
 	ControlJobEndpointStatus  string = "/status"
 )
 
-func (j *ControlJob) JobStart(ctx context.Context) {
+func (j *controlJob) Run(ctx context.Context) {
 
-	log := getLogger(ctx)
+	log := job.GetLogger(ctx)
 	defer log.Info("control job finished")
 
-	daemon := ctx.Value(contextKeyDaemon).(*Daemon)
-
-	l, err := ListenUnixPrivate(j.sockaddr)
+	l, err := helpers.ListenUnixPrivate(j.sockaddr)
 	if err != nil {
 		log.WithError(err).Error("error listening")
 		return
@@ -68,16 +67,12 @@ func (j *ControlJob) JobStart(ctx context.Context) {
 	}})
 	mux.Handle(ControlJobEndpointVersion,
 		requestLogger{log: log, handler: jsonResponder{func() (interface{}, error) {
-			return NewZreplVersionInformation(), nil
+			return version.NewZreplVersionInformation(), nil
 		}}})
 	mux.Handle(ControlJobEndpointStatus,
 		requestLogger{log: log, handler: jsonResponder{func() (interface{}, error) {
-			panic("FIXME") // FIXME
-		}}})
-	mux.Handle("/pulljobreport",
-		requestLogger{log: log, handler: jsonResponder{func() (interface{}, error) {
-			j := daemon.conf.Jobs["debian"]
-			return j.(*PullJob).Report(), nil
+			s := j.jobs.status()
+			return s, nil
 		}}})
 	server := http.Server{Handler: mux}
 

cmd/daemon/daemon.go

@@ -0,0 +1,162 @@
+package daemon
+
+import (
+	"context"
+	"os"
+	"os/signal"
+	"syscall"
+	"sync"
+	"fmt"
+	"github.com/zrepl/zrepl/cmd/daemon/job"
+	"strings"
+	"github.com/zrepl/zrepl/logger"
+	"github.com/zrepl/zrepl/version"
+	"time"
+)
+
+
+func Run(ctx context.Context, controlSockpath string, outlets *logger.Outlets, confJobs []job.Job) {
+
+	ctx, cancel := context.WithCancel(ctx)
+	defer cancel()
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+	go func() {
+		<-sigChan
+		cancel()
+	}()
+
+	log := logger.NewLogger(outlets, 1*time.Second)
+	log.Info(version.NewZreplVersionInformation().String())
+
+	// parse config
+	for _, job := range confJobs {
+		if IsInternalJobName(job.Name()) {
+			panic(fmt.Sprintf("internal job name used for config job '%s'", job.Name())) //FIXME
+		}
+	}
+
+	ctx = job.WithLogger(ctx, log)
+
+	jobs := newJobs()
+
+	// start control socket
+	controlJob, err := newControlJob(controlSockpath, jobs)
+	if err != nil {
+		panic(err) // FIXME
+	}
+	jobs.start(ctx, controlJob, true)
+
+	// start prometheus
+	//var promJob *prometheusJob // FIXME
+	//jobs.start(ctx, promJob, true)
+
+	log.Info("starting daemon")
+
+	// start regular jobs
+	for _, j := range confJobs {
+		jobs.start(ctx, j, false)
+	}
+
+	select {
+		case <-jobs.wait():
+			log.Info("all jobs finished")
+		case <-ctx.Done():
+			log.WithError(ctx.Err()).Info("context finished")
+	}
+	log.Info("daemon exiting")
+}
+
+type jobs struct {
+	wg sync.WaitGroup
+
+	// m protects all fields below it
+	m sync.RWMutex
+	wakeups map[string]job.WakeupChan // by JobName
+	jobs map[string]job.Job
+}
+
+func newJobs() *jobs {
+	return &jobs{
+		wakeups: make(map[string]job.WakeupChan),
+		jobs: make(map[string]job.Job),
+	}
+}
+
+const (
+	logJobField    string = "job"
+	logTaskField   string = "task"
+	logSubsysField string = "subsystem"
+)
+
+func (s *jobs) wait() <-chan struct{} {
+	ch := make(chan struct{})
+	go func() {
+		s.wg.Wait()
+	}()
+	return ch
+}
+
+func (s *jobs) status() map[string]interface{} {
+	s.m.RLock()
+	defer s.m.RUnlock()
+
+	type res struct {
+		name string
+		status interface{}
+	}
+	var wg sync.WaitGroup
+	c := make(chan res, len(s.jobs))
+	for name, j := range s.jobs {
+		wg.Add(1)
+		go func(name string, j job.Job) {
+			defer wg.Done()
+			c <- res{name: name, status: j.Status()}
+		}(name, j)
+	}
+	wg.Wait()
+	close(c)
+	ret := make(map[string]interface{}, len(s.jobs))
+	for res := range c {
+		ret[res.name] = res.status
+	}
+	return ret
+}
+
+const (
+	jobNamePrometheus = "_prometheus"
+	jobNameControl = "_control"
+)
+
+func IsInternalJobName(s string) bool {
+	return strings.HasPrefix(s, "_")
+}
+
+func (s *jobs) start(ctx context.Context, j job.Job, internal bool) {
+	s.m.Lock()
+	defer s.m.Unlock()
+
+	jobLog := job.GetLogger(ctx).WithField(logJobField, j.Name())
+	jobName := j.Name()
+	if !internal && IsInternalJobName(jobName) {
+		panic(fmt.Sprintf("internal job name used for non-internal job %s", jobName))
+	}
+	if internal && !IsInternalJobName(jobName) {
+		panic(fmt.Sprintf("internal job does not use internal job name %s", jobName))
+	}
+	if _, ok := s.jobs[jobName]; ok {
+		panic(fmt.Sprintf("duplicate job name %s", jobName))
+	}
+	s.jobs[jobName] = j
+	ctx = job.WithLogger(ctx, jobLog)
+	ctx, wakeupChan := job.WithWakeup(ctx)
+	s.wakeups[jobName] = wakeupChan
+
+	s.wg.Add(1)
+	go func() {
+		defer s.wg.Done()
+		jobLog.Info("starting job")
+		defer jobLog.Info("job exited")
+		j.Run(ctx)
+	}()
+}

cmd/daemon/job/job.go

@@ -0,0 +1,47 @@
+package job
+
+import (
+	"github.com/zrepl/zrepl/logger"
+	"context"
+)
+
+type Logger = logger.Logger
+
+type contextKey int
+
+const (
+	contextKeyLog contextKey = iota
+	contextKeyWakeup
+)
+
+func GetLogger(ctx context.Context) Logger {
+	if l, ok := ctx.Value(contextKeyLog).(Logger); ok {
+		return l
+	}
+	return logger.NewNullLogger()
+}
+
+func WithLogger(ctx context.Context, l Logger) context.Context {
+	return context.WithValue(ctx, contextKeyLog, l)
+}
+
+func WithWakeup(ctx context.Context) (context.Context, WakeupChan) {
+	wc := make(chan struct{}, 1)
+	return context.WithValue(ctx, contextKeyWakeup, wc), wc
+}
+
+type Job interface {
+	Name() string
+	Run(ctx context.Context)
+	Status() interface{}
+}
+
+type WakeupChan <-chan struct{}
+
+func WaitWakeup(ctx context.Context) WakeupChan {
+	wc, ok := ctx.Value(contextKeyWakeup).(WakeupChan)
+	if !ok {
+		wc = make(chan struct{})
+	}
+	return wc
+}

cmd/daemon/pprof.go

@@ -1,4 +1,4 @@
-package cmd
+package daemon
 
 import (
 	"net/http"

cmd/daemon/prometheus.go

@@ -1,19 +1,21 @@
-package cmd
+package daemon
 
 import (
 	"context"
-	"github.com/mitchellh/mapstructure"
-	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/zrepl/zrepl/zfs"
 	"net"
 	"net/http"
+	"github.com/zrepl/zrepl/cmd/daemon/job"
 )
 
-type PrometheusJob struct {
-	Name   string
-	Listen string
+type prometheusJob struct {
+	listen string
+}
+
+func newPrometheusJob(listen string) *prometheusJob {
+	return &prometheusJob{listen}
 }
 
 var prom struct {
@@ -46,32 +48,19 @@ func init() {
 	prometheus.MustRegister(prom.taskLogEntries)
 }
 
-func parsePrometheusJob(c JobParsingContext, name string, i map[string]interface{}) (j *PrometheusJob, err error) {
-	var s struct {
-		Listen string
-	}
-	if err := mapstructure.Decode(i, &s); err != nil {
-		return nil, errors.Wrap(err, "mapstructure error")
-	}
-	if s.Listen == "" {
-		return nil, errors.New("must specify 'listen' attribute")
-	}
-	return &PrometheusJob{name, s.Listen}, nil
-}
+func (j *prometheusJob) Name() string { return  jobNamePrometheus }
 
-func (j *PrometheusJob) JobName() string { return j.Name }
+func (j *prometheusJob) Status() interface{} { return nil }
 
-func (j *PrometheusJob) JobType() JobType { return JobTypePrometheus }
-
-func (j *PrometheusJob) JobStart(ctx context.Context) {
+func (j *prometheusJob) Run(ctx context.Context) {
 
 	if err := zfs.PrometheusRegister(prometheus.DefaultRegisterer); err != nil {
 		panic(err)
 	}
 
-	log := getLogger(ctx)
+	log := job.GetLogger(ctx)
 
-	l, err := net.Listen("tcp", j.Listen)
+	l, err := net.Listen("tcp", j.listen)
 	if err != nil {
 		log.WithError(err).Error("cannot listen")
 	}

cmd/helpers/helpers.go

@@ -1,10 +1,10 @@
-package cmd
+package helpers
 
 import (
+	"path/filepath"
+	"os"
 	"github.com/pkg/errors"
 	"net"
-	"os"
-	"path/filepath"
 )
 
 func PreparePrivateSockpath(sockpath string) error {